Controlling Mold Growth: It's All About Moisture Control

Because mold can grow on many different types
of materials, it is essential to maintain
effective moisture control within a building. The
fact that molds need moisture to colonize a
surface means that preventing excess moisture in
a building usually will prevent mold from
growing. Once mold has established itself as a
colony, it often can survive in much less
moisture than was required to establish the
colony. Additionally, the reintroduction of even
a slight amount of moisture into an environment
where an inactive mold colony exists can trigger
new growth of the colony.

Moisture can enter a
home through many different means, such as pipe
leaks, roof leaks, high ground water and
condensation. In addition, many daily activities
can produce moisture. Some of these include
cooking, showering and drying clothes. In fact,
people themselves produce about three pints of
water vapor per day while breathing.

Mold growth in a building can be prevented by
practicing effective moisture control procedures.
Examples of moisture control methods include:

Fix broken pipes as soon as they are
discovered and promptly clean all
impacted areas.

Repair leaky roofs as soon as the problem
is found and promptly clean all affected
areas.

Use exhaust fans in kitchens and
bathrooms while showering or cooking to
remove the humidity that these activities
produce.

Vent clothes dryers to the outside.

Put clothes away in closets or drawers
only after they are completely dry.

Leave closet doors open to allow air
circulation.

Do not place objects too close to cool
walls (such as exterior walls) as this
may create a barrier that prevents air
and heat circulation and increases the
likelihood of condensation on the wall
surface.

Use dehumidifiers to remove moisture from
areas with high humidity when ventilation
is not an option (such as when the air
being used to ventilate is of higher
moisture content than the air being
replaced).

Install energy-efficient windows to
reduce window condensation.

Utilize drain tile and a sump pump to
control ground water.

Landscape the area surrounding a building
so that moisture is carried away from the
building.

Ensure that rain gutters are clear of
debris and as leak free as practical.

Extend rain gutter downspouts so they do
not dump water right next to the
building.

Keep sprinklers from hitting a building
(especially open windows).

Take a look at the following papers for a more
thorough look at indoor moisture problems: